An implantable medical device, such as a cardiac pacemaker, may deliver therapy (e.g., electrical stimulation or a drug) to a patient via a medical lead. In the case of pacing and/or defibrillation therapy, for example, a distal end of the lead carrying the electrode may be anchored proximate to a heart of a patient, and the proximal end of the lead may be anchored to or proximate to a pacemaker. If the patient is still growing while the medical device is implanted within the patient, such as in the case of a pediatric patient, the distance between the pacemaker and the electrode at the distal end of the lead may generally increase over time. If, however, both the distal and proximal ends of the lead are substantially fixed, the patient's growth may result in tensile forces that pull on either the distal and/or proximal ends of the lead. It is therefore desirable to develop new devices that address tensile forces.